1. Field of the Invention
The present invention relates to a Multicast and Broadcast Service (MBS). More particularly, the present invention relates to an apparatus and a method for changing an MBS channel of a terminal in a broadband wireless communication system.
2. Description of the Related Art
In an MBS of a conventional mobile Worldwide Interoperability for Microwave Access (WiMAX) system, one channel is associated with a connection having one service flow, which is discriminated by Connection Identification (referred to as CID hereinafter). When a user requests a change from a channel that is currently being received, a conventional terminal performs a Dynamic Service Add (DSA) procedure with a base station in order to receive information (i.e., CID) regarding a new channel. However, this DSA procedure causes delay while the terminal changes its channel.
In order for a terminal to receive a different channel in an MBS of the conventional mobile WiMAX, the terminal should receive all data from a base station and determine whether information regarding an MBS MAP message is included in a DownLink (DL) MAP of a relevant frame. When the information regarding the MBS MAP message is included in the DL MAP, the terminal receives relevant MBS MAP messages using the information regarding the MBS MAP message, determines whether information regarding the different channel is included in the MBS MAP messages, and receives data via the different channel by changing the channel using the information regarding the different channel. In other words, it is not until a terminal receives the DL MAP from the base station that the terminal is able to receive information regarding the different channel. Therefore, when reception coverage of the DL MAP is smaller than that of the MBS, a terminal may not receive information regarding the different channel to which the terminal intends to change. In other words, information regarding a channel change increases. Accordingly, there is a need for an improved apparatus and method for changing an MBS channel of a terminal.